III. The line of cession, described as a meridian line, drawn from the forty-fifth degree of north latitude, south through the most westerly bent or inclination of Lake Ontario, in the deed of cession to the United States of certain territory claimed by the state of New York, lying west of said line, executed March 1, 1781, by James Duane, William Floyd and Alexander McDougal, delegates in Congress of said United States from the said state of New York, in pursuance of an act of the legislature of said state, entitled “An act to facilitate the completion of the articles of confederation and perpetual union among the United States of America,” passed February nineteenth, 1780, which said territory was afterward conveyed by the United States aforesaid to, and became a part of the territory and jurisdiction of the said Commonwealth of Pennsylvania, as the said line was surveyed and marked with posts and monuments of stone in the year 1790, by Andrew Ellicott, who was duly appointed for that purpose by the President of the United States, in pursuance of a resolution of Congress, passed August 19, 1789, which said line, and its prolongation due north into the waters of Lake Erie until it intersects the northern boundary of the United States aforesaid, have since been acknowledged and recognized by the said two states, as a part of the limit of their respective territory and jurisdiction, shall, notwithstanding any possible want of conformity to the verbal description thereof, as contained in said deed of cession, continue to be the boundary or partition line between the said two states, so far as said line so surveyed and marked in 1790 shall extend.